''Ramosmania'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of two

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

of small

tree In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, e.g., including only woody plants with secondary growth, only ...

s in the family

Rubiaceae Rubiaceae () is a family (biology), family of flowering plants, commonly known as the coffee, madder, or bedstraw family. It consists of terrestrial trees, shrubs, lianas, or herbs that are recognizable by simple, opposite leaves with Petiole ( ...

; one is

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

. Both species are endemic to the island of

Rodrigues Rodrigues ( ; Mauritian Creole, Creole: ) is a Autonomous administrative division, autonomous Outer islands of Mauritius, outer island of the Republic of Mauritius in the Indian Ocean, about east of Mauritius. It is part of the Mascarene Isl ...

Mauritius Mauritius, officially the Republic of Mauritius, is an island country in the Indian Ocean, about off the southeastern coast of East Africa, east of Madagascar. It includes the main island (also called Mauritius), as well as Rodrigues, Ag ...

Species

The genus comprises two species: * ''

Ramosmania rodriguesi ''Ramosmania rodriguesi'', commonly known as café marron, is a tree native to the Mauritian island of Rodrigues in the Indian Ocean. The plant has an average size of about and features white five-petal star-shaped flowers. Its French common nam ...

'' * †'' Ramosmania heterophylla'' (extinct)

Cytology

The diploid chromosome count of ''Ramosmania rodriguesi'' is 2n = 22.Kiehn, M., & Berger, A. (2023)
"New chromosome counts on Rubiaceae from Africa and the Western Indian Ocean islands."
Nordic Journal of Botany, e03732.

Conservation

The only remaining species, ''Ramosmania rodriguesi'', was re-discovered by a schoolboy in 1979.Smith, P. (2023, June 1). The loneliest tree in the world. Botanic Gardens Conservation International. Retrieved June 30, 2023, from https://www.bgci.org/news-events/the-loneliest-tree-in-the-world/ After its rediscovery, the local population repeatedly cut off branches of the only remaining tree. To prevent its extinction, cuttings were sent to the Royal Botanic Gardens, Kew. Vegetative propagation was successful, however generative reproduction was not possible, as only functionally male flowers were formed. Later, it was discovered that heat stress could induce the formation of female flowers, which were then successfully pollinated.Seynsche, M. (2009, August 5). Kaffee mit Todessehnsucht. Deutschlandfunk. Retrieved June 30, 2023, from https://www.deutschlandfunk.de/kaffee-mit-todessehnsucht-100.html Cultivated plants have been reintroduced to Rodrigues, but it is still classified as Critically Endangered by the International Union for Conservation of Nature and Natural Resources.World Conservation Monitoring Centre. 1998. ''Ramosmania rodriguesii''. The IUCN Red List of Threatened Species 1998: e.T33659A9801264. https://dx.doi.org/10.2305/IUCN.UK.1998.RLTS.T33659A9801264.en. Accessed on 30 June 2023.

References

External links

* * Rubiaceae genera Octotropideae Flora of Mauritius Endemic flora of Mauritius Flora of Rodrigues Endemic flora of Rodrigues {{Ixoroideae-stub